Sewing machines



Feb. 7, 1956 1. T. SJOGREN 2,733,677

SEWING MACHINES Filed Feb. 15, 1955 4 Sheets-Sheet 1 1 INVENTOR 1? mm mo/e/m/momm BY 6. iv

ATTORNEYS I T SJCGREN SEWING MACHINES Feb. 7, 1956 4 Sheets-Sheet 2 Filed Feb. 13, 1953 IVAN THOR/N/l/S' SJOGREN BY 6 Z ATTORNEYS Feb. 7, 1956 l. T. SJOGREN SEWING MACHINES 4 Sheets-Sheet 3 Filed Feb. 13, 1953 I NVENTOR IVAN THORINIUS SJOGREN ATTORNEYS l. T. SJOGREN 2,733,677

SEWING MACHINES 4 Sheets-Sheet 4 Feb. 7, 1956 Filed Feb. 13, 1955 MW THOR/MM SJOGRN United States Patent SEWING MACHINES Ivan Thorinius Sjiigren, Uddevalla, Sweden Application February 13, 1953, Serial No. 336,73?

7 Claims. (Cl. 112-220) The present invention relates to sewing machines of the kind with a V-shaped frame of which the lower, substantially horisontal, cloth-supporting branch is provided at its free end with a reciprocating cloth-feeding element underneath the path of the work-piece and a number of swingably mounted threaded pickers, and the upper branch of which carries at its free end a transversally disposed driving shaft and mechanism coupled to said shaft and adapted to drive a needle-bar and a cloth-feeder adapted to cooperate with the aforesaid cloth-feeding element, means being provided for transmitting the movement of the driving shaft to the thread pickers and to the cloth-feeding element disposed underneath the path of the work.

The object of the invention is to provide a sewing machine of the kind referred to which is simple in construction and which has a vibrationless running even at high speeds.

The invention is broadly characterised in that the aforesaid movement-transmitting means comprise a shaft or rod extending along the upper branch of the frame and capable of performing axial as well as rocking movements which rod is so coupled to the driving shaft that, as this rotates, the rod be imparted a combined reciprocating axial movement and a rocking rotational movement, and another shaft or rod extending along the lower branch of the frame and also capable of performing axial as well as rocking movements, which rod carries at its one end the thread pickers and is coupled to the clothfeeding element disposed underneath the path of the work, and at its opposite end is socoupled to the firstmentioned rod as to have imparted thereto the combined sliding and rocking movements of the same.

According to a preferable embodiment the rod extending along the upper branch of the frame coincides with a vertical plane forming an angle with a vertical plane perpendicular to the longitudinal direction of the driving shaft, a ring which is rockably and rotationally mounted on a rotatory body eccentrically secured to the driving shaft being linked to an arm projecting radially out from said rod.

At its end adjacent the point of union between the branches of the frame the rod extending along the upper branch of the frame may be provided with a substantially radially projecting arm linked to the free end of an arm projecting substantially radially out from the corresponding end of the rod extending along the lower branch of the frame. One of said arms may be provided at its free end with a ball-shaped portion journalled in a correspondingly shaped seat provided at the free end of the other arm.

The rod extending along the lower shaft of the frame may be linked to one arm of a double-armed lever, the other arm of which is linked to and carries one end of the cloth-feeding element disposed underneath the path of the work. The connection between the rod and the lever arm may preferably comprise a coiled spring with the coils close to each other. The other end of said cloth- "ice feeding element may be supported by a rotationally mounted roller.

An embodiment of the invention is shown in the accompanying drawings wherein Figure 1 is a side elevation of a sewing machine according to the invention; Figure 2 is a top view of the machine with certain parts broken away; Figure 3 is a section on the line I II-III in Figure 2; Figures 4 and 5 show on a larger scale the mechanism for transmitting the movement of the driving shaft to the rod extending along the upper branch of the frame; Figure 6 is a side elevation, likewise on a larger scale, of the cloth-feeding element and the thread-pickers of the machine, and Figure 7 is a section along the line VII-VII in Figure 6. Fig. 8 is an enlarged detailed view of the head of the upper branch of the sewing machine; and Fig. 9 is an enlarged view of the driving shaft forming part of the head.

In the drawings 1 designates the lower branch of the V-shaped frame the upper branch of which is designated by the numeral 2. Transversally disposed in a head 3 provided at the free end of the upper branch 2 there is rotationally mounted a driving shaft 5 provided at its one end with a driving pulley 4. The shaft 5 projects by its other end into a recess 6 provided at one side of the head 3 and housing the mechanisms for driving a presser foot 7, a needle holder 8 and a feeding foot 8a acting on the top surface of the work-piece. These mechanisms may be of conventional kind and comprise according to the embodiment shown a crank 9 secured to the shaft 5 and connected by means of a link 10 to the needle holder 8, and a balance 11 mounted on an eccentric 11a fixed on the shaft 5. To arm 11b of said balance 11 there is linked the top end of an arm 12 carrying the feeding foot 8a and being by means of an elongated slot 12a slidable and rockable on a pin 8b secured to the head 3. The other arm 11c of the balance 11 has a pin 11d passing through an elongated slot 40a in a link 49, which connects 'saidarm 11c with one arm 13b of another two-armed balance 13a, the other arm 130 of which is linked to a rod 13' carrying the pressure foot '7. The arm 13b of the balance 13a is actuated by a coil spring 41 connected to arm which tends to turn the balance 13a anticlockwise according to Fig.8.

When the main shaft 5 is rotating in an anticlockwise direction (according to Fig. 8), the crank 9 imparts to the needle-holder S a reciprocating sliding movement, while the balance 11 imparts to the feeding foot carrying arm 12 a combined swinging and sliding movement and to the presser foot carrying rod 13 a reciprocating sliding movement, so that the presser foot 7 and feeding foot 8a will move in a conventional manner.

On the central portion 1413f the driving shaft 5 (which portion is eccentric in relation to the axis of rotation of the shaft 5) there is secured the inner ring 15 of a spherical ballbearing, and on said ball bearing there is rockably and rotationally mounted a ring 17 provided at its top with a head 16. The upper branch 2 of the frame has a channel 17a through which there is passed a rod 18 slidably and rotationally mounted in bearings 19 (only one being seen in the drawing). The rod 18 which coincides with a vertical plane forming an angle with a vertical plane perpendicular to the longitudinal direction of the shaft 5 (see Figure 2) carries at one end a head 29 secured to the rod 18 and formed with two arms 21 embracing the head 16 of the ring 17 and linked to said head by means of a pin 22 parallel to the rod 18. As the shaft 5 rotates there will be imparted to the rod 18 a combined reciprocating movement in the longitudinal direction and a rocking rotational movement. In a longitudinal channel 23 in the lower branch 1 of the frame there is (in bearings 24) slidably and rotationally mounted a rod 25 to one end of which located in the free end of r V 3 the branch 1 there are secured two radially projecting, arched thread-pickers 26. At the other end of the rod 25, located in a recess 28 in the intermediate portion 27 of the frame, the rod 18 is provided with a radially projecting arm 30 provided at its free end with a cylindrical end slidably inserted in a cylindrical recess provided in the ball-shaped member. 29. To the adjacent end of the other rod 25 there is secured a radially projecting arm 31 provided at its free end with a correspondingly shaped seat 32 which embraces the ball-shaped member 39, which may rotate in the seat. In this manner the sliding and rocking movement of the rod 18 will be transmitted to the rod 25. During the run of the machine the rod 25 will describe a combined reciprocating slidable and rocking rotational movement whereby the thread-pickers 26 are moved between the positions shown in Figures 6 and 7 in full and dotted lines, respectively. In front of the end of the rod 25 to which the thread-pickers 2d are secured there is located one arm 33 of a double-armed lever 35 rockable on a horizontal pin 34 perpendicular to the longitudinal direction of the branch 1 of the frame, and to the other arm 36 of said lever there is linked one end of a cloth-feeding element 37 acting on the bottom side of the work-piece. The other end of the cloth-feeding element 37 is supported by a rotationally mounted roller 38. The rod 25 is connected to the lever arm 33 by means of a coiled spring 39 having the coils close to each other, and said spring transmits the reciprocating axial movement of the rod 25 to the lever 35 and by means of this to the feeding element 37, which is imparted a reciprocating movement in the feeding direction of the work-piece.

What I claim is:

1. An improvement in sewing machines comprising a substantially V-shaped frame, a rod slidably and rotatably extending along one branch of said frame, driven means mounted in the free end of said frame branch connected to and imparting a combined reciprocating axial and a rotationally rocking movement to said rod, a second rod slidably and rotatably extending along the other branch of said frame, means connecting the ends of said rods at the apex of said frame and capable of imparting a combined reciprocating axial and a rotationally rocking movement to said second rod upon and corresponding to the movement of said first rod, a plurality of thread pickers mounted on and extending laterally of the free end of said second rod, a cloth feeding element reciprocally mounted in the free end of said second men tioned branch, means connecting said second mentioned rod to said cloth feeding element for reciprocating the same, a needle rod reciprocally mounted through the free end of said first mentioned branch, a cloth feeder pivotally mounted through the free end of said first mentioned branch for cooperating with said cloth feeding element and means for operating said needle rod and cloth feeder being operatively connected to said driven means.

2. Improvements in sewing machines as claimed in claim 1 wherein said driven means consists of a driven shaft rotatably mounted on the free end of said first mentioned branch and having an eccentric portion relative to the axis of said shaft, a roller bearing secured on said eccentric portion of said driven shaft, a ring rockably and rotationally mounted on said roller bearing, an arm extending radially from said first-mentioned rod and being linked to said ring for being reciprocated and rocked thereby and said first mentioned rod being positioned to coincide with a vertical plane forming an angle with a vertical plane perpendicular to the longitudinal direction of said driven shaft.

3. Improvements in sewing machines as claimed in claim 1 wherein said rod end connecting means consists of an arm extending radially from said first mentioned rod, an arm extending radially from said second mentioned rod and means linking said arms for creating corresponding movements therebetween.

4. Improvements in sewing machines as claimed in claim 1 wherein said rod end connecting means consists of an arm extending radially from said first mentioned rod, said arm having a ball-shaped portion provided at its free end, an arm extending radially from said second mentioned rod having a ball-shaped seat provided at its free end slidably containing said ball-shaped portion of said first arm.

5. Improvements in sewing machines as claimed in claim 1 wherein a double armed lever is pivotally mounted in the free end of said second mentioned branch, means linking one arm of said lever to said second mentioned rod for being pivoted thereby and the other arm of said lever is pivotally connected to said cloth feeding element for reciprocating the same.

6. Improvements in sewing machines as claimed in claim 1 wherein a double armed lever is pivotally mounted in the free end of said second mentioned branch, a tightly coiled spring connects one arm of said lever to an end of said second mentioned rod for pivoting said lever, and the other arm of said lever is pivotally connected to said cloth feeding element for reciprocating the same.

7. Improvements in sewing machines as claimed in claim 1 wherein a double armed lever is pivotally mounted in the free end of said second mentioned branch, means linking one arm of said lever to said second mentioned rod for being pivoted thereby, the other arm of said lever is pivotally connected to and supports an end of said cloth feeding element for reciprocating the same and a roller is rotatably mounted in said second mentioned branch and slidably supports the opposite end of said cloth feeding element.

References Cited in the file of this patent UNITED STATES PATENTS 630,559 Parkes Aug. 8, 1899 1,283,478 De Voe Nov. 5, 1918 1,999,893 Christensen Apr. 30, 1935 FOREIGN PATENTS I 851,714 Germany Oct. 6, 1952 

